This invention relates to vaginal speculums, and is more particularly concerned with an improved speculum having a single control arrangement which enables the physician to release the blades for adjustment of blade aperture (speculum aperture) and/or blade angulation, as desired, simply by loosening a single covering nut, and thereafter to lock the blades at the adjusted aperture and angulation simply by tightening the covering nut. No speculum presently available offers the simplicity and ease of manipulation achieved by this arrangement.
Present state-of-the-art metal speculums have a slot in the upper blade handle which permits variation of the speculum aperture. A first covering nut must be loosened for aperture adjustment and then tightened to maintain the blades at the selected aperture. Blade angulation is adjusted with a thumb lever having a second covering nut. Angulation is increased by pushing down on the thumb lever and then fixed by tightening the second covering nut. At maximum angulation, the second covering nut must be threaded down a full inch in order to maintain the adjusted state. Operation of the two controls is required for both insertion and removal of the speculum, and this is quite tedious for the physician. The operation is even more tedious when a relaxation of the vagina is present.
A plastic speculum is presently available which allows control of blade angulation by a serrated projection selectively cooperable with lower and upper transverse slots in the lower blade handle. To obtain maximum aperture, the projection must be freed from the lower slot, and the upper blade handle then pushed upward to engage the projection in the upper slot. A major disadvantage of this speculum is that the blades can be secured at only maximum or minimum aperture; nothing between is possible. A second major disadvantage is the difficult manipulation required to change from maximum back to minimum aperture. In order to make this adjustment, the serrated projection must be freed from the upper transverse slot, and the upper blade then grasped and moved in a curved pattern back to the minimum aperture or "closed" position of the blades.